What Are Varifocal Glasses?
Varifocal glasses, also known as varifocals, varifocal lenses, PALs, or progressive lenses, have a gradual change in strength from the top of the lens to the bottom with multiple focal points in between. This allows you to see all distances and focus points through just one lens. Varifocal lenses are typically used when you have two prescriptions, one for distance and one for reading.
There are three regions of a varifocal lens which are distant zone, intermediate zone and, near/reading zone. Usually, the upper portion of the varifocal lens is the distant zone and the bottom portion of the varifocal lens is the near or reading zone.
One of the benefits of varifocal glasses is that you do not need to prepare 2 separate pairs of glasses or need to switch between frames for different vision needs.
GlassesShop
It provides men's glasses with good quality and low price. The existing frames have plastic materials to metal. They provide you with a variety of men's glasses like rectangular glasses and round glasses. The glasses have a classic rectangular shape and design. Made of not heavy and durable high-quality materials, they can adapt to a variety of style preferences. A rectangular shape adds clarity, while sharp lines may complement the soft facial features.
Buy Prescription Glasses Online Step By Step
1. Before you can buy glasses online, you’ll need a current glasses prescription.
2. Select an online retailer, comparing online retailers like EyeBuyDirect and KOALAEYE until you find the best fit for your needs.
3. Shop for the perfect frames according to face shape, frame favorites, the budget, etc.
4. Once you’ve found your perfect frames, you’ll enter your eyeglasses prescription and pupillary distance to choose the lenses.
5. Read over the fine print on return/exchange policies and product warranties before you complete your order.
6. Having picked your perfect frames, entered your prescription information, added any lens coatings and upgrades, and checked your online retailer's warranty and return policy, it’s time to complete your order.
How to buy anti-blue light products?
In order to further standardize anti-blue light products and make all kinds of products effectively protect eye health, relevant standards have been formulated. Based on the different effects of blue light in different bands on the human body, the transmittance of blue light in each band is required in the standards.
For example, in the band range of 415-445 nm, the transmission ratio of light is less than or equal to 80%, and more than 445 nm, it is greater than 80%.
What Are the Disadvantages of High-Index Lenses?
This section will show high index lenses disadvantages.
- High index lenses are made from a chemical synthetic blend that’s created through a special manufacturing process. So, high index lenses are expensive than regular lenses. In fact, the price may be more than double that of the traditional counterparts.
- High index lenses can be more brittle than their traditional counterparts and may also be more prone to scrapes and scratches. This can impact their overall durability.
- High index lenses are more reflective than regular lenses, which can make them less effective for brightly lit work environments, outdoor use and nighttime driving on busy highways.
- High index lenses have greater potential for distortion, particularly in your peripheral vision because the high index lenses have a higher Abbe value than prescriptions made from standard plastic or glass.
Advantages of Progressive Lens
Continuous and clear vision throughout the entire process is the advantage of progressive lenses. Because the added value continuously increases gradually in the gradient zone, the wearer can obtain continuous clear vision from the far point to the near point through the gradient lens under the appropriate head position. In line with physiological optics, better adaptation. The appearance is better than that of double-lens and triple-lens. There is no dividing line of sub-sheets, and there is no ring-shaped blind zone and invisible sub-sheets.
For the different brand frames, the price is different.
Prada, Armani, Bvlgari, and other brands belong to the group of high-end eyewear brands (400-800 at a discount if the price is around 00-5000). Poly glasses, Bolon, Prosun, belongs to the middle-end glasses brand group (price 300-00 or so, discount price 300 or so): Serova and other products belong to the high-cost performance glasses brand (price 300 or less).
